1. Technical Field
This disclosure relates generally to a rotational system and, more particularly, to monitoring a dynamic parameter such as torque in the rotational system.
2. Background Information
Horsepower and efficiency of a rotor assembly of a turbine engine may be determined from rotational speed of and torque on a shaft of the rotor assembly using known methodologies. The rotational speed, for example, may be measured using a once per revolution sensor. The torque may be measured using a strain gauge mounted on the shaft. The torque may alternatively be measured with shaft sensors located at opposite ends of the shaft. These shaft sensors, for example, may monitor relative rotational positions of the respective shaft ends to determine shaft windup (e.g., torsional twisting), which is indicative of the torque on the shaft. Error of such systems that measure torque with a strain gauge or two shaft sensors, however, may increase as axial length of the shaft decreases and/or a stiffness of the shaft increases.
There is a need in the art therefore for an improved system for monitoring a dynamic parameter such as torque of a rotor assembly.